Final passage of a gay marriage law in Britain is expected to take place before the end of this week.

Members of parliament's lower House of Commons were expected on Tuesday evening to debate amendments approved in the upper chamber, the House of Lords. Officials said that they expect the bill to clear the chamber and receive royal assent from Queen Elizabeth II on Wednesday or Thursday.

“But we are looking at seeing the first gay weddings in the middle of 2014 because there are various issues to sort out, such as its impact on pensions,” a spokesman for the culture ministry, which is overseeing the new law, told the AFP.

Opponents warned that the issue would haunt the ruling Conservative Party in the general election.

The Coalition for Marriage said passage will “come back to bite” Prime Minister David Cameron in 2015.

Jubilant supporters said passage would provide momentum for similar proposals in the United Kingdom's other two nations, Scotland and Northern Ireland.

According to a YouGov poll for the Sunday Times, 54 percent of Britons favor marriage equality.

Fourteen nations, including 9 European countries, allow gay couples to marry, the latest being France. Gay couples can also marry in some regions of the United States, Mexico and Brazil. A judge in Colombia has paved the way for that nation's first same-sex wedding.